Silencer for typewriting machines



Dec. 30,1924. I 521,050

M.-F. ROBERTSON snENcER FOR rYPEwRnme. MACHINES I FllecfDe. 15, I925 IINVENTOR ATTORNEY Patented Dec. 30, 1924.

UNITED STATE MARIE F. ROBERTSON, OF NEW YORK, N. Y.

SILENCER FOR TYPEWR-ITING MACHINES.

Application filed December 15, 1923.

To all whom it may concern:

Be it known that I, li iiuun F. ROBERTSON, a citizen of the UnitedStates, and a resident of New York, in the county of New York and Stateof New York, have invented certain new and useful Improvements in aSilencer for Typewriting Machines, of which the following is a full.clear, and exact speci fication.

This invention relates more particularly to a class of devices adaptedto be used in conjunction. with typewriting machines.

My invention has for its object primarily to provide a device orsilencer designed to be employed for muifling the sound produced by theparts of typewriting machines when operated, in order to overcome theannoyance to listeners resulting from the noise especially where anumber of the machines are synchronously operated in a single room orcompartment, and which is of a form adapted to be removably applied tothe ma chine to allow of being made and sold independently of thetypewriting apparatus as well as permitting the device to be made invarious sizes and shapes for use upon clifferent types of typewritingmachines. The invention consists essentially of a flat flexible body ofsound muffling material, preferably felt, and the body may besubstantially rectangular or other appropriate shape of a size to permitof being removably disposed for covering the exterior of the walls ofthe frame of a typewriting machine exclusive of the parts of the machinesupporting the finger keys. The body may be divided into flexiblyjointed rear wall, side Wall and front wall sections having suitablecut-outs for accommodating the parts of the machine protruding beyondthe exterior of the frame to allow the device to snugly fit the bodyproper of the machine for serving to obstruct the passage of the wavesof sound produced when the machine is operated.

A further object of the invention is to provide a silencer of a simple,efficient and durable form which may be folded into a compact parcelwhen not in use.

With these and other objects in View, the invention will be hereinaftermore fully explained with reference to the accompanying drawing forminga part of this specification in which similar characters of referenceindicate corresponding parts in all the views,

and will then be pointed out in the claims at the end of thedescription.

Serial No. 680,881.

In the drawing, Figure 1 is a perspective View of a typewriting machineWith one form of silencer embodying my invention applied thereto.

Fig. 2 is a plan view of the silencer when in unfolded position forcovering the frame of a typewriting machine, and

Fig. 3 is a perspective view of the silencer when in folded position forcovering the frame of a typevvriting machine.

The device or silencer has a body 10 which may be made of anyappropriate sound 1nnffling flexible material, though I prefer to makethe body of a sheet or strip of felt of a thickness adapted to obstructthe passage of sound waves. The body may be substantially rectangular,as indicated, or of other suitable shape as well as being of anappropriate size to embrace the exterior of the rear wall 11, side walls12, 13 and front wall 141 of the body, as 15 of a typewriting machine 16which may be of a well known form having the top 17 of its frameoverhanging the walls of the body as well as having the protruding part18 of the frame which supports the finger keys, as 19.

The form of the body 10 of the silencer illustrated is divided into arear wall section 20, side wall sections 21, 22 and front wall sections23, 24:. These sections of the body are flexibly jointed together, at25, 26, 27, 28, and the joints may be provided by stitching or otherwisehingedly fastening the opposed ends of the sections together. The rearsection 20 is substantially rectangular, and this section is of a sizeso that its upper edge closely fits under the overhanging rear edge ofthe top 17 of the frame of the body of the machine. In the upper edge ofthe rear wall section 20 may be a cut-out, as 29, for accommodating apart of the machine, not shown, which protrudes beyond the rear wall 11of the body 15 of the frame of the machine. Each f the side wallsections 21, 22 of the flexib e body 10 is also approximatelyrectangular as well as being of a size so that both sections closely fitunder the overhanging side edges of the top of the frame of the body ofthe-machine, and in the upper edge of each of the side wall sections 21,22 may be spaced cut-outs,-as 30, 31, for accommodating the parts of themachine, as 32, protruding beyond the frame of the machine. Each of thefront wall sections 23, 24 of the flexible body 10 are of combinedshapes and sizes for covering the front wall of the body 15 of the frameof the n'iachine, and in the upper free corner of each of the front wallsections maybe cut-out 33 of a curvature conforming to the archedportions 24 in the upper part of the front wall of the frame of themachine. Also in the free end of each of the front wall sections 28, 24below the cut-out 33 may be a cut-out 35 for accommodating theprotruding part. as 36, of the machine when the front wall sections arein covering positions on the front wall of the frame of the machine.Through the front wall section 23 at its juncture with the side wallsection 21 may be an opening or cut-out, as 37, for accommodating stillanother part, as 38, protruding from, the machine. The body 10 isthereby made of a size to snugly fit in sur rounding); position thefront wall, side walls and rear wall of the body proper of the machinefor serving to muffle the sound of. its parts when operated withoutinterfen ing with the operation of the machine in the usual manner.

In the foregoing description, I have embodied the preferred form of myinvention, but I do not wish to be understood as limiting myselfthereto, as I am aware that modifications may be made therein withoutdeparting from the principle or sacrificing any of the advantages ofthis invention, there fore, I reserve to myself the rightto make suchchanges'as fairly fall within the scope thereof. I

Having thus described my invention, I claim as new and desire to secureby Letters Patentt- 1. A silencer for typewriting machines, having aflat flexible body of sound muifling material including flexibly jointedrear wall and side wall sections for being removably disposed to coverthe rear wall. and side walls of the frame of the machine exclusive ofthe parts of the frame supporting the finger keys and each of saidsections having cut-outs for accommodating parts of the machineprotruding beyond the exterior of the frame.

2. A silencer for typewriting machines,

having a flat flexible body of sound niullliug material includingflexibly jointed rear wall. side wall and front wall sections for beingremovably disposed to cover the rear wall. side walls and front wall ofthe frame of the machine exclusive of the parts of the machinesupporting the finger keys and each of said sections having cut-outs foraccommodating parts of the machine protruding beyond the exterior of theframe.

3. A silencer for typewriting machines. comprising a substantiallyrectangular sheet of felt of relative thickness for obstructing thepassage of waves of sound, said sheet divided into sections flexiblyconnected for being removahly arranged to closely cover the rear walland side walls under the oven hanging upper edge of the frame of theinachine eXclusive of the parts of the frame supporting the finger keys.

l. A silencer for typewriting machines, comprising a substantiallyrectangular sheet of felt of relative thickness for obstructing thepassage of waves of sound, said sheetdivided into sections flexiblyconnected for being remorably arranged to closely cover the rear wall,side walls and front wall under the overhanging upper edge of the frameof the machine exclusive of the parts of the frame supporting the fingerkeys.

5. A silencer for typewriting machines, comprising a substantiallyrectangular sheet of felt of relative thickness for obstructing thepassage of waves of sound, saidshect divided into sections flexiblyconnected for being removably arranged. to closely cover the rear wall.side walls and front wall under the overhanging upper edge of the frameof the machine exclusive of the parts of the frame supporting the fingerkeys and each of said sections having cut-outs for accommodating partsof the machine protruding beyond the exterior of the frame.

This specification signed and witnessed this 14th day of December, A. D.1923.

MARIE F. ROBERTSON. Witnesses L. E. Cmswnnn. J FnuDnuToK ORYEK.

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